【作者】 韩立荣；

【导师】 宗兆锋；

【作者基本信息】 西北农林科技大学 ， 植物病理学， 2006， 硕士

【摘要】 本实验对土壤中诱捕分离得到的6株生防放线菌SC1,SC11,SE2,A3,A4以及153皿内抑菌活性和生物学习性进行了测定,同时对抗逆性强和促生效果的菌株153进行较为系统的研究。选用9种常见的植物病原真菌作为靶标菌,皿内拮抗性测定结果表明,6株生防放线菌均表现出很强的拮抗能力。对受抑制的菌丝进行的显微观察发现,受抑制的靶标真菌基内菌丝不同程度发生了畸变,随着处理时间的延长畸变程度随之加强;6株放线菌对供试的靶标真菌均表现出了不同程度的持续抑菌作用,同一放线菌的持续抑菌作用谱不同,同一靶标菌被持续抑制的放线菌的种类和数量也不同,菌株153表现的持续抑菌作用最强。对6株放线菌的生物学习性研究表明,6株放线菌对供试药品敏感程度有明显差异,只有菌株153对供试的抗生素和杀菌剂均表现出较强的耐受性。6株生防放线菌对3种作物胚根的生长均没有明显抑制作用,并且可在3种作物根际定殖,其中153菌株的定殖效果最好,并表现出对幼苗生长的促进作用。菌株153在番茄和茄子根部、根际土壤和叶面的定殖动态研究结果表明,该菌株无论在番茄还是茄子根部、根际和叶面都可稳定定殖。植物根际定殖数量30d内变化幅度不大,30d后仍维持在较高水平,但均低于原始菌量;在叶面由于生存环境相对恶劣,定殖数量明显低于根际;从不同处理看,菌株153在自然土和灭菌土中都可大量定殖,灭菌土中定殖数量低于自然土中。经过对153菌株的培养特征和生理生化特性分析,初步将其归于链霉菌金色类群。菌株153的温室防病促生研究表明,经153菌株发酵菌液处理的番茄和茄子的株高、鲜重和干重都明显增加,植株体内叶绿素含量和根系活力也显著高于对照。菌株153对温室番茄叶霉病有一定的控制作用,接种前3d喷施拮抗菌的各处理其防病效果远高于接种后3d喷施拮抗菌的各处理,前者防效为61.15%,而后者防效为47.78%。菌株153处理土壤对茄子黄萎病防治效果达到83.72%。更多还原

【Abstract】 The biological characteristic and inhibiting effect of six strains of actinomyces trapped from soil were studied. The results shown that strain 153 having effects of strong tolerance and better promotes growth.Nine pathogenic fungi, including Botrytis cinerea, Colletotrichum gloeosporioides, Fulvia fulvum, Fusarium oxysporum f.sp. niveum, Mucor piriformis, Penicillium expansum, Rhizoctonia solani, Trichothecium roseum and Verticillium dahliae were used to test the antagonistic effects of six biocontrol actinomyces. The results demonstrated that six strains have shown significant inhibiting effect. Morphological of suppressive mycelia on nine target pathogens are observed with microscope. The results indicated that substrate mycelium of target pathogens suppressed with antagonistic actinomyces had been deformed or lysed and the degree of deformation were potentiated as prolonging the antagonistic. All tested actinomycetes had represented persistent inhibiting effects on the target pathogens in different degrees and the same strain of actinomyces had different inhibiting categories of pathogens. The persistent inhibiting effect of strain 153 was best to target pathogens.The biological characteristic studies with six strains shown that they had different sensitivity to the tested antibiotic and fungicides. Strain 153 had strong tolerance to the all tested antibiotic and fungicides. Six strains of actinomyces had no inhibition on the seeds germination of cucumber, tomato and eggplant, and could colonize in rhizosphere. The development of tested plants could be promoted by strain 153.Colonizing dynamics of 153 in rhizosphere, on the leaves and within plants of tomato and eggplant were investigated. The results showed that strain 153 could colonize in rhizosphere, on the leaves and within plants. The colonization number of strain 153 was stable, but the number were always bellow the original one. The colonization results shown that strain 153 could colonized in the natural soil and sterilized soil, and the numbers in the sterilized soil were less than those in the natural soil. On the basis of the morphological features, the physiological and biochemical characteristics, strain 153 was identified to更多还原